Diet and frailty in Norwegian older adults: The Tromsø Study

Abstract

Our population, as a whole, is ageing. With older age increases the risk of poor health and diseases, including increased risk of becoming frail. Frailty is a complex syndrome that arise after gradual loss of physical and/or mental capacity, making individuals less resilient to stressors such as diseases, falls and other unwanted events. Frail individuals have higher risk of ill health, an increased need for health care services and consequently, higher health care costs. Diet is an important risk factor of frailty; however, few studies have investigated the association between dietary intake over time and frailty. The overall aim of this thesis was to investigate the longitudinal association between diet and frailty, and pre-frailty in Norwegian older adults. Using data from the Tromsø Study, we investigated the association between diet in adulthood, and patterns of diet over time, and frailty status in older age. The Nordic and Norwegian Dietary Guidelines define a healthy diet as one ‘rich in whole grains, fruit and vegetables, healthy fats, fish and lean dairy, and low in red and processed meat, sweets, snacks and alcohol’. Such a diet provides an adequate intake of nutrients essential for good health. Specifically, we investigated the effects of i) protein; a nutrient crucial to counteract age-associated loss of muscle mass and function, ii) fish; a rich source of nutrients essential for good health, including omega-3 fatty acids, vitamin D and iodine, and iii) an overall healthy diet over time. Our results showed that individuals who ate in line with the dietary guidelines – regarding protein, fish, and the diet as a whole – from mid-life onwards, had lower risk of pre-frailty and frailty in older age, compared with individuals whose intakes were further from the recommendations. This supports the promotion of a healthy diet from mid-life to facilitate healthier ageing in the Norwegian population.